I really like the fact that you used the different pavement styles so well, and I think the additional exits covered by policemen and barricades really add to Cerulean City's appearance in a logical fashion(An exit through a civilian's house? Why!?) I do feel, though, that the trees leading to Nugget Bridge need some indication that they aren't simply growing straight out of the pavement(Which may require new tiles or to use the ones which border the bike shop's backyard). Speaking of which, I think you might want to make the back of the bike shop a bit sandier, as the grass seems rather out of place for a business. Finally, Cerulean Cave looks very nice with the additional levels, but it feels too small. I'd try making another level of rock face and then having it narrow off.

A test map I drew of an early-game mountain pass(To get a sense of it - Just before a player would get Cut, but they would get Rock Smash closer to mid-game. The cave would lead to a town, as would the north, south, and east paths.)